The present disclosure relates generally to medical devices and methods, such as those useful for inverting and closing a left atrial appendage.
Atrial fibrillation (AF) is the most common cardiac arrhythmia and affects millions of people worldwide, with the incidence expected to increase significantly in coming years. While AF is not a serious cardiac risk factor, it is very significant risk factor for stroke. AF produces a large number of arterial emboli that can enter cerebral circulation and cause stroke. AF is estimated to cause about 25% of all strokes and increases the risk of stroke in an individual by 500% when compared to people with normal sinus rhythm. Over 90% of such embolic strokes originate with clots released from the left atrial appendage (LAA), and a number of procedures and tools have been developed in an attempt to isolate the left atrial appendage and reduce the incidence of stroke, particularly in people suffering from AF.
The left atrial appendage is a windsock-like structure which extends from the left atrium and creates a side chamber which can be a site of increased clot formation and accumulation. There is some evidence that AF can further increase the tendency for clot to accumulate in the LAA, and the rapid contraction of the heart which accompanies AF can initiate the release of emboli and the consequent risk of stroke.
Both percutaneous and intravascular approaches have been proposed for LAA closure. Although some of these devices have now received regulatory approval, such systems are subject to a number of potential drawbacks. In particular, the present systems may be subject to incomplete LAA closure, dislodgement of the device, blood clot formation on the device, and the like. For these reasons, it would be desirable to provide improved LAA closure devices and protocols which produce at least some of these risks.